1. Technical Field
The present invention relates to a light-emitting diode (LED) module, and more particularly, to an LED module, a backlight assembly having the LED module and a display device having the backlight assembly.
2. Discussion of the Related Art
Generally, as liquid crystal display (LCD) panels do not produce light but rather provide an image by blocking light, an LCD display device includes a backlight assembly supplying the LCD panel with light. Many backlight assemblies have traditionally used a fluorescent light source such as a cold cathode fluorescent lamp (CCFL), however, it is becoming increasingly common to use a backlight assembly comprising one or more light emitting diodes (LEDs). Backlight assemblies having light-emitting diodes (LEDs) are widely used for display devices such as mobile LCD devices of mobile communication terminals, digital cameras and computer monitors. A backlight assembly having an LED light source may have a light weight, a thin profile, and other beneficial characteristics.
LED backlight assemblies may provide for either direct illumination or edge illumination. In a direct illumination type display device, the LED of the backlight assembly is disposed behind the display panel from the point of view of a viewer watching the display device. In an edge illumination type display device, the LED of the backlight assembly is disposed adjacent to a side of a light guide plate (LGP) and the LGP guides light from the side of the backlight assembly along the back of the display panel. The edge illuminated LED backlight may include a plurality of LEDs arrayed on a flexible printed circuit board (FPCB) having circuit lines printed on a flexible resin film.
Some of the light produced by the edge illuminated LED backlight might fail to be directed correctly to the desired location behind the LCD panel. This light that is not correctly guided is considered light leakage. Accordingly, some modern edge illuminated LED backlights include light-controlling technology to decrease the leakage of the light emitted from the LED and to guide the light toward an effective display area. This light-controlling technology may add to the structure of the backlight and may accordingly increase cost and manufacturing complexity associated with edge illuminated LED backlight LCD devices.
Additionally, the FPCB on which the LED is mounted may be a source of light leakage. It is also possible for optical sheets to lift away from the LGP and such an occurrence may deteriorate the image quality of the display device.